Information processing apparatus, information processing method, and program

ABSTRACT

An offset angle calculation section calculates an offset amount of a position of a reference screen from a reference position present in a front direction of a user, and a position information correction section corrects a position of an audio object referred with the reference position, in conformity with the position of the reference screen on the basis of the offset amount. Furthermore, an object remapping section remaps the position of the audio object in conformity with a position of a reproduction screen on the basis of the corrected position of the audio object. The present technique can be applied to an information processing apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit under 35U.S.C. § 120 of U.S. patent application Ser. No. 16/265,151, titled“INFORMATION PROCESSING APPARATUS, INFORMATION PROCESSING METHOD, ANDPROGRAM,” filed Feb. 1, 2019, which is a continuation of U.S. patentapplication Ser. No. 15/742,944, titled “INFORMATION PROCESSINGAPPARATUS, INFORMATION PROCESSING METHOD, AND PROGRAM,” filed Jan. 9,2018, now U.S. Pat. No. 10,356,547, which is a National Stage ofInternational Application No. PCT/JP2016/069594, filed in the JapanesePatent Office as a Receiving office on Jul. 1, 2016, which claimspriority to Japanese Patent Application Number 2015-198582, filed in theJapanese Patent Office on Oct. 6, 2015 and Japanese Patent ApplicationNumber 2015-142253, filed in the Japanese Patent Office on Jul. 16,2015, each of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present technique relates to an information processing apparatus, aninformation processing method, and a program, and particularly relatesto an information processing apparatus, an information processingmethod, and a program capable of performing appropriate remapping.

BACKGROUND ART

Conventionally, a Screen-Related Object Element Remapping technique hasbeen adopted in ISO/IEC 23008-3 “3D Audio” standard (see, for example,NPL 1).

According to this technique, in rendering and reproduction of objectaudio, positions of audio objects are remapped (relocated) depending onreference screen information that indicates a position and a magnitudeof a reference screen which serves as a reference and reproductionscreen information that indicates a position and a magnitude of areproduction screen actually reproduced. By doing so, if imagereproduction is performed such that, for example, objects on thereference screen are displayed on the reproduction screen with apositional relation remaining unchanged, it is possible to localizeaudio images of those objects at the same positions as those of theobjects on the reference screen.

CITATION LIST Non Patent Literature

[NPL 1]

ISO/IEC DIS 23008-3 “Information technology-High efficiency coding andmedia delivery in heterogeneous environments-Part 3: 3D audio”

SUMMARY OF THE INVENTION Technical Problem

Meanwhile, the above technique is premised on the fact that a centralposition of the reference screen is placed in front of a user in areproduction space. However, in such a case as when an omnidirectionalimage, for example, that displays an image in all directions of 360° isreproduced or when a part of an entire image is subjected to zoomreproduction, the central position of the reference screen is not alwaysplaced in front of the user depending on situations.

In such a case, when the positions of the audio objects are remapped bythe above technique, the positions after remapping are distorted. Thatis, a distortion occurs in a positional relation among the audio objectsoutside of the reproduction screen, and appropriate remapping cannot berealized.

The present technique has been made in the light of these situations andan object thereof is to be able to perform appropriate remapping.

Solution to Problem

An information processing apparatus according to one aspect of thepresent technique includes an offset calculation section that calculatesan offset amount of a position of a reference screen from a referenceposition present in a front direction of a user, a position correctionsection that corrects a position of an audio object referred with thereference position, in conformity with the position of the referencescreen on the basis of the offset amount, and a remapping section thatremaps the position of the audio object in conformity with a position ofa reproduction screen on the basis of the corrected position of theaudio object.

The offset calculation section can be caused to correct the offsetamount by a predetermined correction value when the reference screen isplaced in a backward direction of the user.

The position correction section can be caused to adjust a correctionvalue used during correction of the position of the audio object when arange of information that indicates the position of the audio object isspecified as a range within a predetermined range.

The position correction section can be caused to correct the position ofthe reference screen on the basis of the offset amount, and theremapping section can be caused to remap the position of the audioobject on the basis of the corrected position of the reference screenand the corrected position of the audio object.

An information processing method or a program according to one aspect ofthe present technique includes the steps of calculating an offset amountof a position of a reference screen from a reference position present ina front direction of a user, correcting a position of an audio objectreferred with the reference position, in conformity with the position ofthe reference screen on the basis of the offset amount, and remappingthe position of the audio object in conformity with a position of areproduction screen on the basis of the corrected position of the audioobject.

According to one aspect of the present technique, an offset amount of aposition of a reference screen from a reference position present in afront direction of a user is calculated, a position of an audio objectreferred with the reference position is corrected in conformity with theposition of the reference screen on the basis of the offset amount, andthe position of the audio object is remapped in conformity with aposition of a reproduction screen on the basis of the corrected positionof the audio object.

Advantageous Effect of Invention

According to one aspect of the present technique, it is possible toperform appropriate remapping.

It is noted that effects are not always limited to those described herebut may be any of effects described in the present disclosure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 depicts positional relations among objects before and afterremapping.

FIG. 2 depicts an example of reference screen information, objectposition information, and reproduction screen information.

FIG. 3 is an explanatory diagram of a change in horizontal positions byremapping.

FIG. 4 depicts an example of object position information afterremapping.

FIG. 5 depicts an example of reference screen information, objectposition information, and reproduction screen information.

FIG. 6 depicts an example of object position information afterremapping.

FIG. 7 depicts positional relations among objects before and afterremapping.

FIG. 8 depicts an example of a configuration of an informationprocessing apparatus.

FIG. 9 depicts an example of object position information afterremapping.

FIG. 10 depicts positional relations among objects before and afterremapping.

FIG. 11 is a flowchart for explaining a remapping process.

FIG. 12 depicts an example of reference screen information, objectposition information, and reproduction screen information.

FIG. 13 depicts an example of object position information afterremapping.

FIG. 14 depicts positional relations among objects before and afterremapping.

FIG. 15 depicts an example of reference screen information, objectposition information, and reproduction screen information.

FIG. 16 depicts an example of object position information afterremapping.

FIG. 17 depicts positional relations among objects before and afterremapping.

FIG. 18 depicts an example of a configuration of an informationprocessing apparatus.

FIG. 19 is a flowchart for explaining a remapping process.

FIG. 20 depicts an example of a configuration of a computer.

DESCRIPTION OF EMBODIMENTS

Embodiments to which the present technique is applied will be describedhereinafter with reference to the drawings.

First Embodiment Remapping

The present technique intends to be able to perform appropriateremapping when audio reproduction is performed by acquiring an audiosignal of each audio object and metadata such as object positioninformation that indicates a position of the audio object. It is notedthat the audio object is often simply referred to as “object,”hereinafter.

For example, when a content is reproduced, a bit stream for reproducingthe content including a dynamic image and sounds accompanying thedynamic image is input to a content reproducing side. This bit stream isobtained by multiplexing, for example, video signals for reproducing adynamic image, an audio signal for reproducing a sound of each object,and various pieces of information such as metadata of each object andreference screen information that indicates a position and a magnitudeof a reference screen used as a reference. The metadata also includes atleast object position information that indicates a position of eachobject in a reproduction space.

Reproduction screen information that indicates a position and amagnitude of a reproduction screen (display screen), which is a screenactually used to reproduce the content, in the reproduction space isalso supplied to the content reproducing side. Then, at a time ofcontent reproduction, remapping of the position of each object indicatedby the object position information is performed on the basis of thereference screen information and the reproduction screen information.

Specifically, the remapping of object positions is performed as depictedin, for example, FIG. 1.

As indicated by an arrow A11, it is assumed that six objects OBJ1 toOBJ6 are located in such a manner as to surround a virtual user U11present at a position of an origin O of the reproduction space. Here,the object OBJ1 to the object OBJ6 are located at positions on thereproduction space indicated by the object position information includedin the metadata.

Furthermore, the reference screen information defines a reference screenRSC11 as a screen used as a reference. In this example, the referencescreen RSC11 is placed in a front direction of the user U11. Note thatit is assumed that the user U11 faces a direction in which the referencescreen RSC11 is present, that is, the front direction.

When the object OBJ1 to the object OBJ6 and the reference screen RSC11are viewed in a top-to-bottom direction in a view indicated by the arrowA11, located positions thereof are depicted in a view indicated by anarrow A12.

In this example, the object OBJ1 and the object OBJ2 are, in particular,placed within the reference screen RSC11. Furthermore, the object OBJ1,the object OBJ3, and the object OBJ5 are located to be bilaterallysymmetric with the object OBJ2, the object OBJ4, and the object OBJ6 ina horizontal direction when being viewed from the user U11.

Therefore, supposing that the dynamic image that constitutes the contentis reproduced on the reference screen RSC11, only the object OBJ1 andthe object OBJ2 are displayed out of the six objects on the referencescreen RSC11.

Now, in the view indicated by the arrow A12, it is assumed that thefront direction when viewed from the user U11, that is, an upwarddirection in the view is a positive direction of an x-axis, a rightdirection when viewed from the user U11 is a positive direction of ay-axis, and a zenith direction when viewed from the user U11, that is, adirection of a near side in the view is a positive direction of az-axis.

It is also assumed that a three-dimensional coordinate system using theorigin O as an origin and having the x-axis, the y-axis, and the z-axisis an xyz coordinate system. It is further assumed that each object andthe reference screen RSC11 are located on a unit sphere a center ofwhich is the origin O and a radius of which is a predetermined distancer (hereinafter, also referred to as “radius r”) from the origin O. Here,the radius r is, for example, 1.

In this case, it is assumed that the positions indicated by the objectposition information and the reference screen information are eachrepresented by a horizontal angle Azimuth that is an angle with respectto the x-axis on an xy plane and a perpendicular angle Elevation that isan angle with respect to the x-axis on an xz plane. Note that, morespecifically, the perpendicular angle Elevation is the angle formedbetween a line that connects a position of interest such as the positionof each object to the origin O and the xy plane. It is further assumedthat positions indicated by the reproduction screen information aresimilarly each represented by a horizontal angle Azimuth and aperpendicular angle Elevation.

Here, as for the horizontal angle Azimuth, it is assumed that thepositive direction of the x-axis is at a horizontal angle Azimuth=0°, aclockwise direction in the view indicated by the arrow A12 is a negativedirection of the horizontal angle Azimuth, and a counterclockwisedirection is a positive direction of the horizontal angle Azimuth.Furthermore, −180°≤Azimuth≤180°.

For example, therefore, the positive direction of the y-axis is at ahorizontal angle Azimuth=−90°, and a negative direction of the x-axis isat a horizontal angle Azimuth=−180°=180°.

As for the perpendicular angle Elevation, it is assumed that a positionin the direction of the x-axis, that is, on the xy plane is at aperpendicular angle Elevation=0°, a rotation direction from the xy planeto the positive direction of the z-axis is a positive direction of theperpendicular angle Elevation, and a rotation direction from the xyplane to a negative direction of the z-axis is a negative direction ofthe perpendicular angle Elevation. Furthermore, −90°≤Elevation≤90°.

For example, therefore, the positive direction of the z-axis is at aperpendicular angle Elevation=90°, and the negative direction of thez-axis is at a perpendicular angle Elevation=−90°.

Moreover, it is assumed hereinafter that a position of an intersectingpoint between the unit sphere and the x-axis on the positive-directionside of the x-axis is a reference position in the reproduction space.That is, the reference position is a position at the horizontal angleAzimuth=0°, the perpendicular angle Elevation=0°, and the radius r=1,and a position in a direction that is exactly in front of the user U11placed in the reproduction space.

In this way, it is assumed that the object position information, thereference screen information, and the reproduction screen informationare each described by the horizontal angle Azimuth and the perpendicularangle Elevation. In this case, when the remapping is performed on thebasis of the object position information, the reference screeninformation, and the reproduction screen information, the locatedposition of each object in the reproduction space is changed asindicated by, for example, arrows A13 and A14.

In this example, the object OBJ1 to the object OBJ6 are relocated inconformity with a reproduction screen PSC11 that is actually used forreproduction.

That is, the object OBJ1 and the object OBJ2 that are placed on thereference screen RSC11 are located on the reproduction screen PSC11 inthe same positional relation as that on the reference screen RSC11.

It is noted that central positions of both the reference screen RSC11and the reproduction screen PSC11 are identical to the referenceposition in this example.

Moreover, the objects are located in a relative positional relation thatis substantially the same as that before remapping. The object OBJ1, theobject OBJ3, and the object OBJ5 are located to be bilaterally symmetricwith the object OBJ2, the object OBJ4, and the object OBJ6 in thehorizontal direction when being viewed from the user U11.

According to such remapping, each object located in conformity with thereference screen RSC11 can be relocated at the position in conformitywith the reproduction screen PSC11 actually used for reproduction. As aresult, at the time of the content reproduction, it is possible toreproduce the content in such a manner, for example, that a sound ofeach object displayed on the reproduction screen PSC11 comes from adirection of the object. Further, as for the objects that are notdisplayed on the reproduction screen PSC11, the content can bereproduced in such a manner that a sound of each of the objects comesfrom an appropriate direction. It is thereby possible to realizeappropriate audio reproduction.

The remapping performed by means of the ordinary Screen-Related ObjectElement Remapping technique will now be described in more detail whilereferring to the six objects depicted in FIG. 1 by way of example.

It is assumed, for example, that information depicted in FIG. 2 is givenas the reference screen information of the reference screen RSC11, theobject position information of the object OBJ1 to the object OBJ6, andthe reproduction screen information of the reproduction screen PSC11.

In FIG. 2, the reference screen information and the object positioninformation are depicted in a part indicated by an arrow Q11, and thereproduction screen information is depicted in a part indicated by anarrow Q12. In addition, in the views of the information, a numericalvalue of the horizontal angle Azimuth or the perpendicular angleElevation is described in each of right-hand side fields.

In this example, the reference screen information is information thatindicates the position and the magnitude of the reference screen RSC11,that is, positions of upper, lower, left, and right ends of thereference screen RSC11.

Specifically, in fields for the reference screen information, characters“Azimuth left end” and “Azimuth right end” indicate the positions of theleft-hand side end and the right-hand side end of the reference screenRSC11 in FIG. 1, respectively, and “29.0” and “−29.0” are described ashorizontal angles Azimuth that indicate those positions. The left-handside end and the right-hand side end of the reference screen RSC11 inFIG. 1 are often referred to as “left end” and “right end” of thereference screen RSC11, hereinafter.

Furthermore, in the fields for the reference screen information,characters “Elevation upper end” and “Elevation lower end” indicate thepositions of the upper side end and the lower side end of the referencescreen RSC11 in FIG. 1, respectively, and “17.5” and “−17.5” aredescribed as perpendicular angles Elevation that indicate thosepositions. The upper side end and the lower side end of the referencescreen RSC11 in FIG. 1 are often referred to as “upper end” and “lowerend” of the reference screen RSC11, hereinafter.

The object position information of each of the objects OBJ1 to OBJ6 isalso depicted in the part indicated by the arrow Q11. Specifically, inrespective fields for “OBJ1” to “OBJ6,” the positions of the object OBJ1to the object OBJ6 are described.

For example, in fields for the object OBJ1 which is denoted by acharacter “OBJ1,” characters “Azimuth” and “Elevation” indicatehorizontal and perpendicular positions of the object OBJ1, respectively,and “20.0” and “10.0” are described as the horizontal angle Azimuth andthe perpendicular angle Elevation that indicate those positions.

Furthermore, the reproduction screen information is depicted in the partindicated by the arrow Q12.

In this example, the reproduction screen information is information thatindicates the position and the magnitude of the reproduction screenPSC11, that is, positions of upper, lower, left, and right ends of thereproduction screen PSC11.

Specifically, in fields for the reproduction screen information,characters “Azimuth left end” and “Azimuth right end” indicate thepositions of the left-hand side end and the right-hand side end of thereproduction screen PSC11 in FIG. 1, respectively, and “14.5” and“−14.5” are described as horizontal angles Azimuth that indicate thosepositions. The left-hand side end and the right-hand side end of thereproduction screen PSC11 in FIG. 1 are often referred to as “left end”and “right end” of the reproduction screen PSC11, hereinafter.

Furthermore, in the fields for the reproduction screen information,characters “Elevation upper end” and “Elevation lower end” indicate thepositions of the upper side end and the lower side end of thereproduction screen PSC11 in FIG. 1, respectively, and “8.5” and “−8.5”are described as perpendicular angles Elevation that indicate thosepositions. The upper side end and the lower side end of the reproductionscreen PSC11 in FIG. 1 are often referred to as “upper end” and “lowerend” of the reproduction screen PSC11, hereinafter.

It is understood from the reproduction screen information indicated bythe arrow Q12 that the reproduction screen PSC11 is a screen (displayscreen) having the magnitude substantially half of that of the referencescreen RSC11.

When the reference screen information, the object position information,and the reproduction screen information described above are given,calculation is conducted as represented by the following Equations (1)and (2) to calculate the positions of the objects after remapping in theordinary Screen-Related Object Element Remapping technique.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 1} \right\rbrack & \; \\{\phi^{\prime} = \left\{ \begin{matrix}\begin{matrix}{\frac{\phi_{right}^{repro} + {180{^\circ}}}{\phi_{right}^{nominal} + {180{^\circ}}} \cdot} \\{\left( {\phi + {180{^\circ}}} \right) - {180{^\circ}}}\end{matrix} & {for} & {{{- 180}{^\circ}} \leq \phi < \phi_{right}^{nominal}} \\\begin{matrix}{\frac{\phi_{left}^{repro} - \phi_{right}^{repro}}{\phi_{left}^{nominal} - \phi_{right}^{nominal}} \cdot} \\{\left( {\phi - \phi_{right}^{nominal}} \right) + \phi_{right}^{repro}}\end{matrix} & {for} & {\phi_{right}^{nominal} \leq \phi < \phi_{left}^{nominal}} \\\begin{matrix}{\frac{{180{^\circ}} - \theta_{left}^{repro}}{{180{^\circ}} - \theta_{left}^{nominal}} \cdot} \\{\left( {\phi - \phi_{left}^{nominal}} \right) + \phi_{left}^{repro}}\end{matrix} & {for} & {\phi_{left}^{nominal} \leq \phi < {180{^\circ}}}\end{matrix} \right.} & (1) \\\left\lbrack {{Math}.\mspace{14mu} 2} \right\rbrack & \; \\{\theta^{\prime} = \left\{ \begin{matrix}\begin{matrix}{\frac{\theta_{bottom}^{repro} + {90{^\circ}}}{\theta_{bottom}^{nominal} + {90{^\circ}}} \cdot} \\{\left( {\theta + {90{^\circ}}} \right) - {90{^\circ}}}\end{matrix} & {for} & {{{- 90}{^\circ}} \leq \theta < \theta_{bottom}^{nominal}} \\\begin{matrix}{\frac{\theta_{top}^{repro} - \theta_{bottom}^{repro}}{\theta_{top}^{nominal} - \theta_{bottom}^{nominal}} \cdot} \\{\left( {\theta - \theta_{bottom}^{nominal}} \right) + \theta_{bottom}^{repro}}\end{matrix} & {for} & {\theta_{bottom}^{nominal} \leq \theta < \theta_{top}^{nominal}} \\\begin{matrix}{\frac{{90{^\circ}} - \theta_{top}^{repro}}{{90{^\circ}} - \theta_{top}^{nominal}} \cdot} \\{\left( {\theta - \theta_{top}^{nominal}} \right) + \theta_{top}^{repro}}\end{matrix} & {for} & {\theta_{top}^{nominal} \leq \theta < {90{^\circ}}}\end{matrix} \right.} & (2)\end{matrix}$

Note that, in Equation (1), φ indicates the horizontal position of eachobject before remapping, that is, the horizontal angle Azimuth includedin the object position information, and φ′ indicates the horizontalangle Azimuth that indicates the horizontal position of the object afterremapping.

Furthermore, in Equation (1) φ_(left) ^(nominal) and φ_(right)^(nominal) indicate the horizontal angles Azimuth that indicate thehorizontal positions of the left end and the right end of the referencescreen RSC11, and φ_(left) ^(repro) and φ_(right) ^(repro) indicate thehorizontal angles Azimuth that indicate the horizontal positions of theleft end and the right end of the reproduction screen PSC11.

In Equation (2), θ indicates the perpendicular position of each objectbefore remapping, that is, the perpendicular angle Elevation included inthe object position information, and θ′ indicates the perpendicularangle Elevation that indicates the perpendicular position of the objectafter remapping.

Furthermore, in Equation (2), θ_(top) ^(nominal) and θ_(bottom)^(nominal) indicate the perpendicular angles Elevation that indicate theperpendicular positions of the upper end and the lower end of thereference screen RSC11, and θ_(top) ^(repro) and θ_(bottom) ^(repro)indicate the perpendicular angles Elevation that indicate theperpendicular positions of the upper end and the lower end of thereproduction screen PSC11.

The horizontal angle Azimuth indicating the horizontal position of eachobject after remapping is calculated as represented by above Equation(1), and the perpendicular angle Elevation indicating the perpendicularposition of the object after remapping is calculated as represented byabove Equation (2).

In remapping by calculation represented by Equations (1) and (2), theobjects within the reference screen RSC11 are subjected to remapping insuch a manner that those objects just fall within the reproductionscreen PSC11 while a positional relation between the objects remainsunchanged. In addition, the objects outside of the reference screenRSC11 are subjected to remapping in response to a positional relationbetween the ends of the reference screen RSC11 and those of thereproduction screen PSC11.

In calculation represented by Equation (1), the horizontal position isremapped, for example, as depicted in FIG. 3. Note that, in FIG. 3, ahorizontal axis denotes a horizontal angle φ of each object beforeremapping, and a vertical axis denotes a horizontal angle φ′ of theobject after remapping.

In this example, a position indicated by a horizontal angle φ_(right)^(nominal) is remapped to a position indicated by a horizontal angleφ_(right) ^(repro). In addition, a position indicated by a horizontalangle φ_(left) ^(nominal) is remapped to a position indicated by ahorizontal angle φ_(left) ^(repro), and positions between the positionindicated by the horizontal angle φ_(right) ^(nominal) and the positionindicated by the horizontal angle φ_(left) ^(nominal) are linearlyremapped.

A position indicated by a horizontal angle φ=−180° remains unchanged asa position indicated by a horizontal angle φ′=−180° even afterremapping, and positions between the position indicated by thehorizontal angle φ=−180° and the position indicated by the horizontalangle φ_(right) ^(nominal) are linearly remapped.

Likewise, a position indicated by a horizontal angle φ=180° remainsunchanged as a position indicated by a horizontal angle φ′=180° evenafter remapping, and positions between the position indicated by thehorizontal angle φ_(left) ^(nominal) and the position indicated by thehorizontal angle φ=180° are linearly remapped.

Therefore, when calculation represented by Equations (1) and (2) isconducted on the basis of the reference screen information, the objectposition information, and the reproduction screen information depictedin FIG. 2, positions depicted in FIG. 4 are obtained as positions of theobjects after remapping. In other words, object position informationdepicted in FIG. 4 is obtained by remapping.

FIG. 4 depicts the object position information of the object OBJ1 to theobject OBJ6 after remapping. Specifically, in respective fields for“OBJ1” to “OBJ6,” the positions of the object OBJ1 to the object OBJ6are described.

For example, in fields for the object OBJ1 which is denoted by thecharacter “OBJ1,” characters “Azimuth” and “Elevation” indicatehorizontal and perpendicular positions of the object OBJ1 afterremapping, respectively, and “10.0” and “4.9” are described as thehorizontal angle Azimuth and the perpendicular angle Elevation thatindicate those positions.

The horizontal angle Azimuth “10.0” and the perpendicular angleElevation “4.9” of this object OBJ1 indicate the horizontal angle φ′ andthe perpendicular angle θ′ of the object OBJ1 after remapping,respectively.

As can be understood from the positions of the objects depicted in FIG.4, even after remapping, the object OBJ1, the object OBJ3, and theobject OBJ5 are located to be bilaterally symmetric with the objectOBJ2, the object OBJ4, and the object OBJ6 in the horizontal directionwhen being viewed from the user U11. That is, it is understood thatremapping has been performed appropriately.

Meanwhile, the ordinary Screen-Related Object Element Remappingtechnique is premised on the fact that the reference screen RSC11 isplaced in front of the user U11, that is, the central position of thereference screen RSC11 is identical to the reference position. In otherwords, it is not supposed that the central position of the referencescreen RSC11 is a position other than the reference position.

Owing to this, when the central position of the reference screen RSC11is a position other than the reference position and remapping isperformed as usual, the positional relation among the objects outside ofthe reference screen RSC11 is distorted.

Specifically, when remapping is performed by the calculation representedby Equations (1) and (2) while reference screen information, objectposition information, and reproduction screen information depicted inFIG. 5, for example, are given, object position information of theobjects after remapping is that as depicted in FIG. 6. It is noted thatFIGS. 5 and 6 correspond to FIGS. 2 and 4 and description of similarparts in FIGS. 5 and 6 to those in FIGS. 2 and 4 will be omitted asappropriate.

In FIG. 5, reference screen information of the reference screen RSC11and object position information of the object OBJ1 to the object OBJ6are depicted in a part indicated by an arrow Q21.

In this example, a position of the reference screen RSC11 indicated bythe reference screen information is a position obtained by rotating theposition depicted in the example of FIG. 2 by as much as 30° in thepositive direction of the horizontal angle Azimuth. That is, in theexample of FIG. 2, the central position of the reference screen RSC11 isidentical to the reference position, whereas in the example depicted inFIG. 5, the central position of the reference screen RSC11 is a positionindicated by a horizontal angle Azimuth=30° and a perpendicular angleElevation=0°.

Likewise, in the example depicted in FIG. 5, a position of each objectindicated by the object position information is a position obtained byrotating the position of the same object depicted in the example of FIG.2 by as much as 30° in the positive direction of the horizontal angleAzimuth.

Therefore, a relative positional relation between the reference screenRSC11 and each object in the example depicted in FIG. 2 is the same asthat in the example depicted in FIG. 5.

Furthermore, reproduction screen information is depicted in a partindicated by an arrow Q22, and this reproduction screen information isthe same as the reproduction screen information depicted in FIG. 2.

While the object position information depicted in FIG. 6 is obtained byremapping based on the reference screen information, the object positioninformation, and the reproduction screen information as described above,it is understood from this object position information that thepositional relation among the objects are asymmetrical.

Note that, in FIG. 6, the positions of the object OBJ1 to the objectOBJ6 are described in fields for “OBJ1” to “OBJ6,” respectively.

Before remapping, the object OBJ1, the object OBJ3, and the object OBJ5are located to be bilaterally symmetric with the object OBJ2, the objectOBJ4, and the object OBJ6 with respect to a segment that connects theorigin O to the central position of the reference screen RSC11 in thehorizontal direction.

On the other hand, in the example depicted in FIG. 6, it is understoodfrom the horizontal angles Azimuth that the object OBJ1 and the objectOBJ2 located within the reference screen RSC11 are bilaterally symmetricwith each other with respect to a segment that connects the origin O tothe central position of the reproduction screen PSC11 in the horizontaldirection even after remapping.

However, it is understood that the object OBJ3 and the object OBJ4located outside of the reference screen RSC11 are not bilaterallysymmetric with each other with respect to the segment that connects theorigin O to the central position of the reproduction screen PSC11 in thehorizontal direction, and the object OBJ5 and the object OBJ6 locatedoutside of the reference screen RSC11 are not bilaterally symmetric witheach other with respect to the segment in the horizontal direction. Thatis, it is understood that the positions of the objects after remappingare not appropriate positions and the positional relation among theobjects is distorted.

A pattern diagram of the positional relations among the objects beforeremapping and after remapping in this example is that depicted in FIG.7. It is noted that parts corresponding to those in FIG. 1 are denotedby the same reference symbols in FIG. 7 and description of the partswill be omitted as appropriate.

In FIG. 7, the reference screen RSC11 and the object OBJ1 to the objectOBJ6 before remapping are depicted in parts indicated by arrows A21 andA22. On the other hand, the reproduction screen PSC11 and the objectOBJ1 to the object OBJ6 after remapping are depicted in parts indicatedby arrows A23 and A24.

In remapping, it is expected that the objects are subjected to remappingin such a manner that the positional relation among the objects viewedfrom the reproduction screen PSC11 is substantially the same as thepositional relation among the objects viewed from the reference screenRSC11 before remapping.

In this example, the relative positional relation among the object OBJ1to the object OBJ6 before remapping is the same as that in the exampledepicted in FIG. 1, and a position of the reproduction screen PSC11 isalso the same as that in the example depicted in FIG. 1. It is,therefore, expected that the object OBJ1 to the object OBJ6 afterremapping are relocated at the same positions as those of the objectsdepicted in FIG. 1.

However, as is understood from FIG. 7, as for the relative positionalrelation among the object OBJ3 to the object OBJ6 placed outside of thereference screen RSC11 before remapping, the relative positionalrelation greatly changes between before remapping and after remapping.The object positions of the object OBJ5 and the object OBJ6, inparticular, are greatly misaligned.

Owing to this, when audio signals of the objects are subjected torendering on the basis of the object position information obtained byremapping, audio images of the objects outside of the reproductionscreen PSC11 are localized at positions different from those at whichthe objects are originally supposed to be present at the time of soundreproduction.

To address the problem, therefore, the present technique intends to beable to perform appropriate remapping even if the central position ofthe reference screen RSC11 differs from the reference position byappropriately correcting the object position information and thereference screen information.

Example of Configuration of Information Processing Apparatus

FIG. 8 depicts an example of a configuration of one embodiment of aninformation processing apparatus to which the present technique isapplied.

An information processing apparatus 11 depicted in FIG. 8 includes anoffset angle calculation section 21, a position information correctionsection 22, and an object remapping section 23.

The reference screen information, the object position information ofeach object, and the reproduction screen information are supplied tothis information processing apparatus 11 from outside.

It is assumed herein that the reference screen information includes, forexample, the horizontal angles that indicate the positions of the leftend and the right end of the reference screen RSC11 and theperpendicular angles that indicate the positions of the upper end andthe lower end of the reference screen RSC11. The reference screeninformation is information that indicates the position and the magnitudeof the reference screen RSC11 while the reference position present inthe front direction of the user U11 is used as the reference.

Likewise, it is assumed that the reproduction screen informationincludes the horizontal angles that indicate the positions of the leftend and the right end of the reproduction screen PSC11 and theperpendicular angles that indicate the positions of the upper end andthe lower end of the reproduction screen PSC11. This reproduction screeninformation is, similarly, information that indicates the position andthe magnitude of the reproduction screen PSC11 while the referenceposition is used as the reference.

Furthermore, the object position information of each object is assumedto include the horizontal angle and the perpendicular angle thatindicate the position of the object. The object position information isinformation that indicates the position of each object while thereference position present in the front direction of the user U11 isused as the reference.

The offset angle calculation section 21 calculates a horizontal angleformed between the front direction of the user U11 present in thereproduction space, that is, the direction from the origin O to thereference position and a direction from the origin O to the centralposition of the reference screen RSC11 as an offset angle on the basisof the supplied reference screen information, and supplies the offsetangle to the position information correction section 22.

The offset angle of the reference screen RSC11 is a horizontal angleAzimuth that indicates a misalignment amount of the central position ofthe reference screen RSC11 from the reference position in a direction ofthe horizontal angle Azimuth. That is, the offset angle is informationthat indicates an offset amount of the reference screen RSC11 from thereference position present in the front direction of the user U11. Notethat, while the offset angle that is the horizontal angle is describedherein as an example of the information indicating the offset amount,the information indicating the offset amount may be any otherinformation.

The position information correction section 22 corrects the referencescreen information and the object position information supplied fromoutside on the basis of the offset angle supplied from the offset anglecalculation section 21, and supplies resultant corrected referencescreen information and corrected object position information to theobject remapping section 23.

The object remapping section 23 performs remapping of the objectposition information, that is, each object position on the basis of thereproduction screen information supplied from outside and the correctedreference screen information and the corrected object positioninformation supplied from the position information correction section22, and outputs resultant object position information.

Processes by Each Section

Processes by the sections that constitute the information processingapparatus 11 will now be described more specifically.

First, the offset angle calculation section 21 calculates an offsetangle φ_(offset_value) by conducting calculation represented by, forexample, the following Equation (3) on the basis of the suppliedreference screen information.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 3} \right\rbrack & \; \\{\phi_{offset\_ value} = \frac{\phi_{left}^{nominal} + \phi_{right}^{nominal}}{2}} & (3)\end{matrix}$

Note that, in Equation (3), φ_(left) ^(nominal) and φ_(right) ^(nominal)indicate the horizontal angles Azimuth that indicate the positions ofthe left end and the right end of the reference screen RSC11. Theinformation φ_(left) ^(nominal) and φ_(right) ^(nominal) is included inthe reference screen information.

Furthermore, the position information correction section 22 corrects thereference screen information on the basis of the offset angleφ_(offset_value) in such a manner that the central position of thereference screen RSC11 becomes identical to the reference position. Thatis, the position information correction section 22 calculates thecorrected reference screen information by calculation represented by thefollowing Equations (4) and (5).

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 4} \right\rbrack & \; \\{\phi_{offset\_ left}^{nominal} = {\phi_{left}^{nominal} - \phi_{offset\_ value}}} & (4) \\\left\lbrack {{Math}.\mspace{14mu} 5} \right\rbrack & \; \\{\phi_{offset\_ right}^{nominal} = {\phi_{right}^{nominal} - \phi_{offset\_ value}}} & (5)\end{matrix}$

Note that, in Equation (4), φ_(left) ^(nominal) indicates the horizontalangle Azimuth that indicates the position of the left end of thereference screen RSC11, and φ_(offset_left) ^(nominal) indicates ahorizontal angle Azimuth after correcting the horizontal angle φ_(left)^(nominal) using the offset angle φ_(offset_value).

That is, φ_(offset_left) ^(nominal) indicates the horizontal angleAzimuth that indicates the position of the left end of the correctedreference screen RSC11.

Moreover, in Equation (5), φ_(right) ^(nominal) indicates the horizontalangle Azimuth that indicates the position of the right end of thereference screen RSC11, and φ_(offset_right) ^(nominal) indicates ahorizontal angle Azimuth after correcting the horizontal angle φ_(right)^(nominal) using the offset angle φ_(offset_value).

That is, φ_(offset_right) ^(nominal) indicates the horizontal angleAzimuth that indicates the position of the right end of the correctedreference screen RSC11.

Therefore, the horizontal angle φ_(left) ^(nominal) included in thereference screen information is corrected by calculation represented byEquation (4), and the horizontal angle φ_(right) ^(nominal) included inthe reference screen information is corrected by calculation representedby Equation (5).

At a time of correcting the reference screen information, only thehorizontal angles φ_(left) ^(nominal) and φ_(right) ^(nominal) arecorrected while the perpendicular angles that indicate the positions ofthe upper end and the lower end of the reference screen RSC11 are notcorrected.

Such a process for calculating the corrected reference screeninformation is a process for rotating the reference screen RSC11 by asmuch as the offset angle φ_(offset_value), that is, by as much as amisalignment of the central position of the reference screen RSC11 fromthe reference position. Through this process, the reference screeninformation is corrected in such a manner that the central position ofthe reference screen RSC11 becomes identical to the reference position.

Furthermore, the position information correction section 22 corrects theobject position information on the basis of the offset angleφ_(offset_value) in such a manner that the positions of the objects arecorrected (moved) in conformity with correction (movement) of theposition of the reference screen RSC11, that is, correction of thereference screen information. That is, the position informationcorrection section 22 calculates the corrected object positioninformation by calculation represented by the following Equation (6).[Math. 6]ϕ_(offset)=ϕ−ϕ_(offset_value)  (6)

Note that, in Equation (6), φ indicates the horizontal angle Azimuth ofeach object included in the object position information, and φ_(offset)indicates a horizontal angle Azimuth obtained by correcting thehorizontal angle φ using the offset angle φ_(offset_value). That is,φ_(offset) indicates the horizontal angle Azimuth that indicates thecorrected object position.

Therefore, the horizontal angle φ included in the object positioninformation is corrected by calculation represented by Equation (6). Ata time of correcting the object position information, only thehorizontal angle φ is corrected while the perpendicular angle thatindicates the perpendicular position of the object is not corrected.

Such a process for calculating the corrected object position informationis a process for rotating the position of each object by as much as theoffset angle φ_(offset_value).

Through this process, the position of each object is corrected inconformity with the position of the reference screen RSC11. Morespecifically, the position of each object is corrected in conformitywith correction of the central position of the reference screen RSC11.Owing to this, the relative position of each object to the referencescreen RSC11 has no change between before and after the correction ofthe reference screen information and the object position information.

When the corrected reference screen information and the corrected objectposition information are obtained as described so far, the objectremapping section 23 performs remapping. That is, the position of eachobject is remapped in conformity with the position of the reproductionscreen PSC11.

At this time, the corrected reference screen information and thecorrected object position information that indicate the positionalrelation between the reference screen RSC11 and the objects serve asinformation that indicates a positional relation when the referenceposition is set identical to the central position of the referencescreen RCS11.

Therefore, using the corrected reference screen information and thecorrected object position information can prevent distortions of theobject positions even if the object positions are remapped by similarcalculation to that conducted in the ordinary Screen-Related ObjectElement Remapping technique. That is, it is possible to realizeappropriate remapping.

Specifically, the object remapping section 23 calculates the objectposition information after remapping by conducting calculationrepresented by the following Equation (7) on the basis of the correctedreference screen information, the reproduction screen information, andthe corrected object position information.

$\begin{matrix}{\mspace{76mu}\left\lbrack {{Math}.\mspace{14mu} 7} \right\rbrack} & \; \\{\phi^{\prime} = \left\{ \begin{matrix}\begin{matrix}{\frac{\phi_{right}^{repro} + {180{^\circ}}}{\phi_{offset\_ right}^{nominal} + {180{^\circ}}} \cdot} \\{\left( {\phi_{offset} + {180{^\circ}}} \right) - {180{^\circ}}}\end{matrix} & {for} & {{{- 180}{^\circ}} \leq \phi_{offset} < \phi_{offset\_ right}^{nominal}} \\\begin{matrix}{\frac{\phi_{left}^{repro} - \phi_{right}^{repro}}{\phi_{offset\_ left}^{nominal} - \phi_{offset\_ right}^{nominal}} \cdot} \\{\left( {\phi_{offset} - \phi_{offset\_ right}^{nominal}} \right) + \phi_{right}^{repro}}\end{matrix} & {for} & {\phi_{offset\_ right}^{nominal} \leq \phi_{offset} < \phi_{offset\_ left}^{nominal}} \\\begin{matrix}{\frac{{180{^\circ}} - \theta_{left}^{repro}}{{180{^\circ}} - \theta_{offset\_ left}^{nominal}} \cdot} \\{\left( {\phi_{offset} - \phi_{offset\_ left}^{nominal}} \right) + \phi_{left}^{repro}}\end{matrix} & {for} & {\phi_{offset\_ left}^{nominal} \leq \phi_{offset} < {180{^\circ}}}\end{matrix} \right.} & (7)\end{matrix}$

Note that, in Equation (7), φ′ indicates the horizontal angle Azimuththat indicates the horizontal position of each object after remapping,and φ_(offset) indicates the horizontal position of the object beforeremapping, that is, the horizontal angle Azimuth included in thecorrected object position information.

Furthermore, in Equation (7) φ_(offset_left) ^(nominal) andφ_(offset_right) ^(nominal) indicate the horizontal angles Azimuth thatindicate the corrected horizontal positions of a left end and a rightend of the reference screen RSC11. That is, φ_(offset_left) ^(nominal)and φ_(offset_right) ^(nominal) indicate the horizontal angles Azimuthof the left end and the right end of the reference screen RSC11 includedin the corrected reference screen information.

Moreover, in Equation and φ_(left) ^(repro) and φ_(right) ^(repro)indicate the horizontal angles Azimuth that indicate the horizontalpositions of the left end and the right end of the reproduction screenPSC11.

Further, more specifically, in determining the remapped object positioninformation of each object, the object remapping section 23 conductscalculation represented by Equation (2) described above on the basis ofthe corrected reference screen information, the reproduction screeninformation, and the corrected object position information. Theperpendicular angle θ′ that indicates the remapped perpendicularposition of the object included in the object position information afterremapping is thereby obtained.

By performing the processes described above, the information processingapparatus 11 can perform appropriate remapping.

Specifically, when the information processing apparatus 11 performsremapping while the reference screen information, the object positioninformation, and the reproduction screen information depicted in, forexample, FIG. 5 are given, object position information depicted in FIG.9 is obtained as the object position information after remapping.

Note that, in FIG. 9, in respective fields for “OBJ1” to “OBJ6,” theremapped object position information of the object OBJ1 to the objectOBJ6, that is, horizontal angles Azimuth and perpendicular anglesElevation of positions of the objects after remapping are depicted.

For example, in fields for the object OBJ1 which is denoted by thecharacter “OBJ1,” characters “Azimuth” and “Elevation” indicatehorizontal and perpendicular positions of the object OBJ1 afterremapping, respectively, and “10.0” and “4.9” are described as thehorizontal angle Azimuth and the perpendicular angle Elevation thatindicate those positions. The horizontal angle Azimuth “10.0” and theperpendicular angle Elevation “4.9” are the horizontal angle φ′calculated as represented by Equation (7) and the perpendicular angle θ′calculated as represented by Equation (2), respectively.

In the example depicted in FIG. 9, the relative positional relationamong all the objects OBJ1 to OBJ6 before remapping is substantially thesame as that after remapping.

That is, it is understood that the object OBJ1 and the object OBJ2located within the reference screen RSC11 are bilaterally symmetric witheach other with respect to a segment that connects the origin O to acentral position of the reproduction screen PSC11 in the horizontaldirection even after remapping.

Moreover, it is understood that the object OBJ3 and the object OBJ4located outside of the reference screen RSC11 are bilaterally symmetricwith each other with respect to the segment that connects the origin Oto the central position of the reproduction screen PSC11 in thehorizontal direction, and the object OBJ5 and the object OBJ6 locatedoutside of the reference screen RSC11 are bilaterally symmetric witheach other with respect to the segment in the horizontal direction. Thatis, it is understood that the positions of all the objects afterremapping are appropriate positions.

A pattern diagram of the positional relations among the objects beforeremapping and after remapping in this example is that depicted in FIG.10. It is noted that parts corresponding to those in FIG. 1 are denotedby the same reference symbols in FIG. 10 and description of the partswill be omitted as appropriate.

In FIG. 10, the reference screen RSC11 and the object OBJ1 to the objectOBJ6 before remapping are depicted in parts indicated by arrows A31 andA32. More specifically, the reference screen RSC11 is located at theposition indicated by the uncorrected reference screen information, andthe object OBJ1 to the object OBJ6 are located at the positionsindicated by the uncorrected object position information.

On the other hand, the reproduction screen PSC11 and the object OBJ1 tothe object OBJ6 after remapping are depicted in parts indicated byarrows A33 and A34.

In this example, the reference screen RSC11 and the object OBJ1 to theobject OBJ6 before remapping indicated by the arrows A31 and A32 arelocated at the same positions as those in the example depicted in FIG.7.

Moreover, it is understood that in the parts indicated by the arrows A33and A34, the object OBJ1, the object OBJ3, and the object OBJ5 afterremapping are bilaterally symmetric with the object OBJ2, the objectOBJ4, and the object OBJ6 after remapping with respect to the segmentthat connects the origin O to the central position of the reproductionscreen PSC11 in the horizontal direction. That is, it is understood thatthe positional relation among the objects viewed from the centralposition of the screen before remapping is substantially the same asthat after remapping, and remapping has been performed appropriately.

Description of Remapping Process

A remapping process performed by the information processing apparatus 11will next be described with reference to the flowchart of FIG. 11.

In Step S11, the offset angle calculation section 21 calculates theoffset angle φ_(offset_value) on the basis of the supplied referencescreen information, and supplies the offset angle φ_(offset_value) tothe position information correction section 22.

Specifically, the offset angle calculation section 21 calculates theoffset angle φ_(offset_value) by conducting calculation represented byEquation (3).

In Step S12, the position information correction section 22 corrects thereference screen information and the object position informationsupplied from outside on the basis of the offset angle φ_(offset_value)supplied from the offset angle calculation section 21.

For example, the position information correction section 22 corrects thereference screen information by conducting calculation represented byEquations (4) and (5) from the offset angle φ_(offset_value) and thereference screen information, and supplies the resultant correctedreference screen information to the object remapping section 23.

Furthermore, the position information correction section 22 corrects theobject position information by conducting calculation represented byEquation (6) from the offset angle  _(offset_value) and the objectposition information, and supplies the resultant corrected objectposition information to the object remapping section 23.

In Step S13, the object remapping section 23 performs remapping of eachobject position on the basis of the reproduction screen informationsupplied from outside, and the corrected reference screen informationand the corrected object position information supplied from the positioninformation correction section 22.

For example, the object remapping section 23 calculates the objectposition information that indicates the remapped positions of theobjects by conducting calculation represented by Equations (2) and (7)on the basis of the corrected reference screen information, thereproduction screen information, and the corrected object positioninformation. The object remapping section 23 then outputs the objectposition information obtained as described above to a subsequent stage,and the remapping process is ended.

In this way, the information processing apparatus 11 performs remappingafter correcting the reference screen information and the objectposition information. By doing so, it is possible to perform appropriateremapping without dependence on the located position of the referencescreen RSC11.

First Modification of First Embodiment Remapping

Meanwhile, as specified in ISO/IEC 23008-3 “3D Audio” standard, a rangeof each of the horizontal angle φ_(left) ^(nominal) of the left end andthe horizontal angle φ_(right) ^(nominal) of the right end of thereference screen RSC11 and the horizontal angle φ of each object isoften specified to be equal to or greater than −180° and equal to orsmaller than 180°.

In such a case, it is necessary to appropriately correct the horizontalangles so that the horizontal angles are values within a preset range,that is, values equal to or greater than −180° and equal to or smallerthan 180° at a time of calculating the corrected reference screeninformation and the corrected object position information.

Furthermore, when the range of each of the horizontal angles φ_(left)^(nominal), φ_(right) ^(nominal), and φ is specified to be equal to orgreater than −180° and equal to or smaller than 180° and the referencescreen RSC11 is located in a backward direction of the user U11, thatis, located in the negative direction of the x-axis when being viewedfrom the user U11, the horizontal angles φ_(left) ^(nominal) andφ_(right) ^(nominal) often satisfy φ_(left) ^(nominal)<φ_(right)^(nominal). In such a case, it is necessary to appropriately correct theoffset angle φ_(offset_value) by an appropriate correction value at atime of calculating the offset value φ_(offset_value).

Note that it is assumed hereafter that the horizontal angles φ_(left)^(nominal) and φ_(right) ^(nominal) are in a state of satisfyingφ_(left) ^(nominal)<φ_(right) ^(nominal) unless specified otherwise whenthe reference screen RSC11 is placed in the backward direction of theuser U11.

When the range of each of the horizontal angles φ_(left) ^(nominal),φ_(right) ^(nominal), and φ is specified to fall within the range equalto or greater than −180° and equal to or smaller than 180° in advance,remapping may be performed as follows.

Note that description will be continued hereinafter while specificallyreferring to a case in which reference screen information, objectposition information, and reproduction screen information depicted inFIG. 12 are given by way of example. In addition, FIG. 12 corresponds toFIG. 2 and description of similar parts in FIG. 12 to those in FIG. 2will be omitted as appropriate.

In FIG. 12, the reference screen information of the reference screenRSC11 and the object position information of the object OBJ1 to theobject OBJ6 are depicted in a part indicated by an arrow Q31.

In this example, a position of the reference screen RSC11 indicated bythe reference screen information is a position obtained by rotating theposition depicted in the example of FIG. 2 by as much as 180° in thedirection of the horizontal angle Azimuth. That is, in the example ofFIG. 2, the central position of the reference screen RSC11 is identicalto the reference position, whereas in the example depicted in FIG. 12,the central position of the reference screen RSC11 is a positionindicated by a horizontal angle Azimuth=180° and a perpendicular angleElevation=0°.

Likewise, in the example depicted in FIG. 12, a position of each objectindicated by the object position information is a position obtained byrotating the position of the same object depicted in the example of FIG.2 by as much as 180° in the direction of the horizontal angle Azimuth.

Therefore, a relative positional relation between the reference screenRSC11 and each object in the example depicted in FIG. 2 is the same asthat in the example depicted in FIG. 12.

Furthermore, the reproduction screen information is depicted in a partindicated by an arrow Q32, and this reproduction screen information isthe same as the reproduction screen information depicted in FIG. 2.

When the reference screen information, the object position information,and the reproduction screen information described above are given, theoffset angle calculation section 21 may calculate the offset angleφ_(offset_value) as represented by the following Equation (8) in placeof Equation (3) described above.

$\begin{matrix}{\mspace{79mu}\left\lbrack {{Math}.\mspace{14mu} 8} \right\rbrack} & \; \\{\phi_{offset\_ value} = \left\{ \begin{matrix}\frac{\phi_{left}^{nominal} + \phi_{right}^{nominal}}{2} & {for} & {\phi_{right}^{nominal} \leq \phi_{left}^{nominal}} \\\frac{{360{^\circ}} + \phi_{left}^{nominal} + \phi_{right}^{nominal}}{2} & {for} & {\phi_{left}^{nominal} < \phi_{right}^{nominal}}\end{matrix} \right.} & (8)\end{matrix}$

Note that, in Equation (8), φ_(left) ^(nominal) and φ_(right) ^(nominal)indicate the horizontal angles Azimuth that indicate the positions ofthe left end and the right end of the reference screen RSC11.

In Equation (8), when the horizontal angles φ_(left) ^(nominal) andφ_(right) ^(nominal) satisfy φ_(left) ^(nominal)<φ_(right) ^(nominal),that is, the reference screen RSC11 is present in the backwarddirection, 180° is added to the angle determined by Equation (3) as acorrection value to obtain a final offset angle φ_(offset_value).

The reason is as follows. When the reference screen RSC11 is present inthe backward direction and the offset angle φ_(offset_value) iscalculated as represented by Equation (3), the same angle as that whenthe reference screen RSC11 is present in the front direction is obtainedas the offset angle φ_(offset_value). Owing to this, it is necessary toadd 180° as the correction value to accurately correct the offset angle.

Furthermore, in Equation (8), when the horizontal angles φ_(left)^(nominal) and φ_(right) ^(nominal) do not satisfy φ_(left)^(nominal)<φ_(right) ^(nominal), that is, the reference screen RSC11 isnot present in the backward direction, the offset angle φ_(offset_value)is calculated in the similar manner to that represented by Equation (3)described above.

When the offset angle φ_(offset_value) is calculated as represented byEquation (8), the position information correction section 22 maycalculate the corrected reference screen information as represented bythe following Equations (9) and (10) in place of Equations (4) and (5).Likewise, the position information correction section 22 may calculatethe corrected object position information as represented by Equation(11) in place of Equation (6).

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 9} \right\rbrack & \; \\{\phi_{offset\_ left}^{nominal} = \left\{ \begin{matrix}{\phi_{left}^{nomial} - \phi_{offset\_ value} + {360{^\circ}}} & {for} & {\phi_{left}^{nominal} < \left( {\phi_{offset\_ value} - {180{^\circ}}} \right)} \\{\phi_{left}^{nomial} - \phi_{offset\_ value}} & {for} & \begin{matrix}{\left( {\phi_{offset\_ value} - {180{^\circ}}} \right) \leq \phi_{left}^{nomial} \leq} \\\left( {\phi_{offset\_ value} + {180{^\circ}}} \right)\end{matrix} \\{\phi_{left}^{nomial} - \phi_{offset\_ value} - {360{^\circ}}} & {for} & {\left( {{180{^\circ}} + \phi_{offset\_ value}} \right) < \phi_{left}^{nominal}}\end{matrix} \right.} & (9) \\\left\lbrack {{Math}.\mspace{14mu} 10} \right\rbrack & \; \\{\phi_{offset\_ right}^{nominal} = \left\{ \begin{matrix}{\phi_{right}^{nomial} - \phi_{offset\_ value} + {360{^\circ}}} & {for} & {\phi_{right}^{nominal} < \left( {\phi_{offset\_ value} - {180{^\circ}}} \right)} \\{\phi_{right}^{nomial} - \phi_{offset\_ value}} & {for} & \begin{matrix}{\left( {\phi_{offset\_ value} - {180{^\circ}}} \right) \leq \phi_{right}^{nominal} \leq} \\\left( {\phi_{offset\_ value} + {180{^\circ}}} \right)\end{matrix} \\{\phi_{right}^{nomial} - \phi_{offset\_ value} - {360{^\circ}}} & {for} & {\left( {{180{^\circ}} + \phi_{offset\_ value}} \right) < \phi_{right}^{nominal}}\end{matrix} \right.} & (10) \\\left\lbrack {{Math}.\mspace{14mu} 11} \right\rbrack & \; \\{\phi_{offset} = \left\{ \begin{matrix}{\phi - \phi_{offset\_ value} + {360{^\circ}}} & {for} & {\phi < \left( {\phi_{offset\_ value} - {180{^\circ}}} \right)} \\{\phi - \phi_{offset\_ value}} & {for} & \begin{matrix}{\left( {\phi_{offset\_ value} - {180{^\circ}}} \right) \leq \phi \leq} \\\left( {\phi_{offset\_ value} + {180{^\circ}}} \right)\end{matrix} \\{\phi - \phi_{offset\_ value} - {360{^\circ}}} & {for} & {\left( {{180{^\circ}} + \phi_{offset\_ value}} \right) < \phi}\end{matrix} \right.} & (11)\end{matrix}$

Note that, in Equations (9) to (11), φ_(offset_value) indicates theoffset angle φ_(offset_value). Furthermore, in Equation (9), φ_(left)^(nominal) indicates the horizontal angle Azimuth that indicates theposition of the left end of the reference screen RSC11, andφ_(offset_left) ^(nominal) indicates a horizontal angle Azimuth aftercorrecting the horizontal angle φ_(left) ^(nominal) using the offsetangle φ_(offset_value).

In Equation (10), φ_(right) ^(nominal) indicates the horizontal angleAzimuth that indicates the position of the right end of the referencescreen RSC11, and φ_(offset_right) ^(nominal) indicates a horizontalangle Azimuth after correcting the horizontal angle φ_(right) ^(nominal)using the offset angle φ_(offset_value).

Moreover, in Equation (11), φ indicates the horizontal angle Azimuththat indicates the horizontal position of each object included in theobject position information, and φ_(offset) indicates a horizontal angleAzimuth obtained after correcting the horizontal angle φ using theoffset angle φ_(offset_value).

For example, in Equation (9), when φ_(left)^(nominal)<φ_(offset_value)−180°, that is, when φ_(left)^(nominal)−φ_(offset_value)<−180°, 360° is added to the horizontal angledetermined by Equation (4) described above to obtain the finalhorizontal angle φ_(offset_left) ^(nominal).

In such a situation, when the horizontal angle φ_(offset_left)^(nominal) is obtained as represented by Equation (4), a value of thehorizontal angle φ_(offset_left) ^(nominal) that is originally supposedto be equal to or greater than −180° and equal to or smaller than 108°becomes smaller than −180°. To address the problem, in calculationrepresented by Equation (9), when φ_(left)^(nominal)<φ_(offset_value)−180°, 360° is added to the horizontal angleobtained as represented by Equation (4) as the correction value toaccurately correct the horizontal angle φ_(offset_left) ^(nominal).

Furthermore, in Equation (9), when φ_(offset_value)−180°≤φ_(left)^(nominal)≤φ_(offset_value)+180°, that is, when −180°≤φ_(left)^(nominal)−φ_(offset_value)≤180°, calculation is conducted in a similarmanner as that represented by Equation (4). Moreover, in Equation (9),when φ_(offset_value)+180° value<φ_(left) ^(nominal), that is, whenφ_(left) ^(nominal)−φ_(offset_value)>180°, the value of the horizontalangle φ_(offset_left) ^(nominal) becomes greater than 180°. Owing tothis, similarly to the case of φ_(left)^(nominal)<φ_(offset_value)−180°, −360° is added as the correction valueto accurately correct the horizontal angle φ_(offset_left) ^(nominal).

Furthermore, in not only Equation (9) but Equation (10) or (11), thecorrection is performed as needed similarly to the case of Equation (9).

In this way, to add 360° or −360° as the correction value depending onthe corrected horizontal angle using the offset angle φ_(offset_value)for each piece of information such as φ_(left)^(nominal)−φ_(offset_value), that is, as needed at a time of correctingthe reference screen information and the object position information canbe restated as a process for adjusting the correction value used duringcorrection of the reference screen RSC11 or each object position.

When the corrected reference screen information and the corrected objectposition information are calculated as described above, the objectremapping section 23 calculates object position information afterremapping as represented by Equations (2) and (7).

For example, when remapping described above is performed while thereference screen information, the object position information, and thereproduction screen information depicted in, for example, FIG. 12 aregiven, object position information depicted in FIG. 13 is obtained asthe object position information after remapping.

Note that, in FIG. 13, in respective fields for “OBJ1” to “OBJ6,” theremapped object position information of the object OBJ1 to the objectOBJ6, that is, horizontal angles Azimuth and perpendicular anglesElevation of positions of the objects after remapping are depicted.

For example, in fields for the object OBJ1 which is denoted by thecharacter “OBJ1,” characters “Azimuth” and “Elevation” indicatehorizontal and perpendicular positions of the object OBJ1 afterremapping, respectively, and “10.0” and “4.9” are described as thehorizontal angle Azimuth and the perpendicular angle Elevation thatindicate those positions. The horizontal angle Azimuth “10.0” and theperpendicular angle Elevation “4.9” are the horizontal angle φ′calculated as represented by Equation (7) and the perpendicular angle θ′calculated as represented by Equation (2), respectively.

In the example depicted in FIG. 13, the relative positional relationamong all the objects OBJ1 to OBJ6 before remapping is substantially thesame as that after remapping.

That is, it is understood that the object OBJ1 and the object OBJ2, theobject OBJ3 and the object OBJ4, and the object OBJ5 and the object OBJ6are bilaterally symmetric with each other with respect to the segmentthat connects the origin O to the central position of the reproductionscreen PSC11 in the horizontal direction even after remapping.

A pattern diagram of the positional relations among the objects beforeremapping and after remapping in this example is that depicted in FIG.14. It is noted that parts corresponding to those in FIG. 1 are denotedby the same reference symbols in FIG. 14 and description of the partswill be omitted as appropriate.

In FIG. 14, the reference screen RSC11 and the object OBJ1 to the objectOBJ6 before remapping are depicted in parts indicated by arrows A41 andA42. More specifically, the reference screen RSC11 is located at theposition indicated by the uncorrected reference screen information, andthe object OBJ1 to the object OBJ6 are located at the positionsindicated by the uncorrected object position information.

On the other hand, the reproduction screen PSC11 and the object OBJ1 tothe object OBJ6 after remapping are depicted in parts indicated byarrows A43 and A44.

In this example, the position of the reference screen RSC11 in the partsindicated by the arrows A41 and A42 is in the backward direction of theuser U11.

Moreover, it is understood that in the parts indicated by the arrows A43and A44, the object OBJ1, the object OBJ3, and the object OBJ5 afterremapping are bilaterally symmetric with the object OBJ2, the objectOBJ4, and the object OBJ6 after remapping with respect to the segmentthat connects the origin O to the central position of the reproductionscreen PSC11 in the horizontal direction. That is, it is understood thatthe positional relation among the objects viewed from the centralposition of the screen before remapping is substantially the same asthat after remapping, and remapping has been performed appropriately.

As described above, when the range of each of the horizontal anglesφ_(left) ^(nominal), φ_(right) ^(nominal), and φ is specified to fallwithin the range equal to or greater than −180° and equal to or smallerthan 180°, the offset angle calculation section 21 calculates the offsetangle φ_(offset_value) by conducting calculation represented by Equation(8) in Step S11 of the remapping process described with reference toFIG. 11.

Furthermore, in Step S12, the position information correction section 22corrects the reference screen information by conducting calculationrepresented by Equations (9) and (10), and corrects the object positioninformation by conducting calculation represented by Equation (11).Then, in Step S13, the object remapping section 23 calculates the objectposition information that indicates the remapped positions of theobjects by conducting calculation represented by Equations (2) and (7).

In this way, the information processing apparatus 11 can performappropriate remapping even when the range of each of the horizontalangles φ_(left) ^(nominal), φ_(right) ^(nominal), and φ is specified tofall within the range equal to or greater than −180° and equal to orsmaller than 180°.

Second Modification of First Embodiment Remapping

Note that the example in which the central position of the reproductionscreen PSC11 is identical to the reference position has been describedabove as a concrete example. However, even when the central position ofthe reproduction screen PSC11 is not identical to the referenceposition, it is possible to perform appropriate remapping by conductingcorrection using an offset angle of the reproduction screen as follows.

Note that description will be continued hereinafter while specificallyreferring to a case in which reference screen information, objectposition information, and reproduction screen information depicted inFIG. 15 are given by way of example. In addition, FIG. 15 corresponds toFIG. 5 and description of similar parts in FIG. 15 to those in FIG. 5will be omitted as appropriate.

In FIG. 15, the reference screen information of the reference screenRSC11 and the object position information of the object OBJ1 to theobject OBJ6 are depicted in a part indicated by an arrow Q41. Thereference screen information and the object position information of theobject OBJ1 to the object OBJ6 are the same as the reference screeninformation and the object position information of the object OBJ1 tothe object OBJ6 depicted in FIG. 5.

Furthermore, the reproduction screen information is depicted in a partindicated by an arrow Q42.

In this example, a position of the reproduction screen PSC11 indicatedby the reproduction screen information is a position obtained byrotating the position depicted in the example of FIG. 2 by as much as180° in the direction of the horizontal angle Azimuth. That is, in theexample of FIG. 2, the central position of the reproduction screen PSC11is identical to the reference position, whereas in the example depictedin FIG. 15, the central position of the reproduction screen PSC11 is aposition indicated by a horizontal angle Azimuth=180° and aperpendicular angle Elevation=0°.

When the reference screen information, the object position information,and the reproduction screen information described above are given, theoffset angle calculation section 21 calculates the offset angle _(offset_value) and also calculates a reproduction screen offset angleφ_(repro_offset_value) by conducting calculation represented by, forexample, the following Equation (12).

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 12} \right\rbrack & \; \\{\phi_{{repro\_ offset}{\_ value}} = \frac{\phi_{left}^{repro} + \phi_{right}^{repro}}{2}} & (12)\end{matrix}$

Note that, in Equation (12), φ_(left) ^(repro) and φ_(right) ^(repro)indicate the horizontal angles Azimuth that indicate the positions ofthe left end and the right end of the reproduction screen PSC11. Theinformation φ_(left) ^(repro) and φ_(right) ^(repro) is included in thereproduction screen information.

Furthermore, in addition to correction of the reference screeninformation and correction of the object position information describedabove, the position information correction section 22 corrects thereproduction screen information on the basis of the reproduction screenoffset angle φ_(repro_offset_value) in such a manner that the centralposition of the reproduction screen PSC11 becomes identical to thereference position. That is, the corrected reproduction screeninformation is calculated by calculation represented by the followingEquations (13) and (14).[Math. 13]ϕ_(offset_left) ^(repro)=ϕ_(left) ^(repro)−ϕ_(repro_offset_value)  (13)[Math. 14]ϕ_(offset_right) ^(repro)=ϕ_(right)^(repro)−ϕ_(repro_offset_value)  (14)

Note that, in Equation (13), φ_(left) ^(repro) indicates the horizontalangle Azimuth that indicates the position of the left end of thereproduction screen PSC11, and  _(offset_left) ^(repro) indicates ahorizontal angle Azimuth after correcting the horizontal angle φ_(left)^(repro) using the reproduction screen offset angleφ_(repro_offset_value). That is, φ_(offset_left) ^(repro) indicates thehorizontal angle Azimuth that indicates the corrected position of theleft end of the reproduction screen PSC11.

Moreover, in Equation (14), φ_(right) ^(repro) indicates the horizontalangle Azimuth that indicates the position of the right end of thereproduction screen PSC11, and φ_(offset_right) ^(repro) indicates ahorizontal angle Azimuth after correcting the horizontal angle φ_(right)^(repro) using the reproduction screen offset angleφ_(repro_offset_value). That is, φ_(offset_right) ^(repro) indicates thehorizontal angle Azimuth that indicates the corrected position of theright end of the reproduction screen PSC11.

Therefore, the horizontal angle φ_(left) ^(repro) included in thereproduction screen information is corrected by the calculationrepresented by Equation (13), and the horizontal angle φ_(right)^(repro) included in the reproduction screen information is corrected bythe calculation represented by Equation (14).

Such a process for calculating the corrected reference screeninformation is a process for rotating the reproduction screen PSC11 byas much as the reproduction screen offset angle φ_(repro_offset_value),that is, by as much as a misalignment of the central position of thereproduction screen PSC11 from the reference position. Through thisprocess, the reproduction screen information is corrected in such amanner that the central position of the reproduction screen PSC11becomes identical to the reference position.

Note that the reproduction screen PSC11 the position of which has beencorrected in such a manner that the central position becomes identicalto the reference position is also referred to as “corrected reproductionscreen PSC11′,” hereinafter.

When the corrected reproduction screen information as well as thecorrected reference screen information and the corrected object positioninformation is obtained as described above, the object remapping section23 performs remapping. That is, the position of each object is remappedin conformity with the position of the corrected reproduction screenPSC11′.

Specifically, the object remapping section 23 calculates the objectposition information after remapping by conducting calculationrepresented by the following Equation (15) on the basis of the correctedreference screen information, the corrected reproduction screeninformation, and the corrected object position information.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 15} \right\rbrack & \; \\{\phi^{\prime} = \left\{ \begin{matrix}\begin{matrix}{\frac{\phi_{offset\_ right}^{repro} + {180{^\circ}}}{\phi_{offset\_ right}^{repro} + {180{^\circ}}} \cdot} \\{\left( {\phi_{offset} + {180{^\circ}}} \right) - {180{^\circ}}}\end{matrix} & {for} & {{{- 180}{^\circ}} \leq \phi_{offset} < \phi_{offset\_ right}^{nominal}} \\\begin{matrix}{\frac{\phi_{offset\_ left}^{repro} - \phi_{offset\_ right}^{repro}}{\phi_{offset\_ left}^{nominal} - \phi_{offset\_ right}^{nominal}} \cdot} \\{\left( {\phi_{offset} - \phi_{offset\_ right}^{nominal}} \right) + \phi_{offset\_ right}^{nominal}}\end{matrix} & {for} & {\phi_{offset\_ right}^{nominal} \leq \phi_{offset} < \phi_{offset\_ left}^{nominal}} \\\begin{matrix}{\frac{{180{^\circ}} - \phi_{offset\_ left}^{repro}}{{180{^\circ}} - \phi_{offset\_ left}^{repro}} \cdot} \\{\left( {\phi_{offset} - \phi_{offset\_ left}^{nominal}} \right) + \phi_{offset\_ left}}\end{matrix} & {for} & {\phi_{offset\_ left}^{nominal} \leq \phi_{offset} < {180{^\circ}}}\end{matrix} \right.} & (15)\end{matrix}$

Note that, in Equation (15), φ′ indicates the horizontal angle Azimuththat indicates the horizontal position of each object after remapping,and φ_(offset) indicates the horizontal position of the object beforeremapping, that is, the horizontal angle Azimuth included in thecorrected object position information.

Furthermore, in Equation (15), φ_(offset_left) ^(nominal) andφ_(offset_right) ^(nominal) indicate the horizontal angles Azimuth thatindicate the corrected horizontal positions of the left end and theright end of the reference screen RSC11. That is, φ_(offset_left)^(nominal) and φ_(offset_right) ^(nominal) indicate the horizontalangles Azimuth of the left end and the right end of the reference screenRSC11 included in the corrected reference screen information.

Moreover, in Equation (15), φ_(offset_left) ^(repro) andφ_(offset_right) ^(repro) indicate the horizontal angles Azimuth thatindicate the horizontal positions of the left end and the right end ofthe corrected reproduction screen PSC11′.

The object position information after remapping obtained here is for thecorrected reproduction screen PSC11′. That is, the information is theobject position information when the central position of thereproduction screen PSC11 is identical to the reference position.Actually, however, the reproduction screen PSC11 is at the positionindicated by φ_(left) ^(repro) and φ_(right) ^(repro) included in thereproduction screen information, and is rotated by as much as thereproduction screen offset angle φ_(repro_offset_value). Therefore,calculation is conducted as represented by the following Equation (16),and the object position information after remapping is corrected to thatfor the actual reproduction screen PSC11.[Math. 16]ϕ″=ϕ′+ϕ_(repro_offset_value)  (16)

Note that, in Equation (16), φ′ indicates the horizontal angle Azimuthincluded in the object position information after remapping of eachobject calculated for the corrected reproduction screen PSC11′, and φ″indicates a horizontal angle after correcting the horizontal angle φ′using the reproduction screen offset angle φ_(repro_offset_value). Thatis, φ″ indicates the horizontal angle Azimuth included in the correctedobject position information after remapping.

Each object position after remapping is thereby corrected in conformitywith the position of the reproduction screen PSC11.

When remapping described hereinabove is performed while the referencescreen information, the object position information, and thereproduction screen information depicted in, for example, FIG. 15 aregiven, object position information depicted in FIG. 16 is obtained asthe object position information after remapping.

Note that, in FIG. 16, in respective fields for “OBJ1” to “OBJ6,” theremapped object position information of the object OBJ1 to the objectOBJ6, that is, horizontal angles Azimuth and perpendicular anglesElevation of positions of the objects after remapping are depicted.

For example, in fields for the object OBJ1 which is denoted by thecharacter “OBJ1,” characters “Azimuth” and “Elevation” indicatehorizontal and perpendicular positions of the object OBJ1 afterremapping, respectively, and “−170.0” and “4.9” are described as thehorizontal angle Azimuth and the perpendicular angle Elevation thatindicate those positions. The horizontal angle Azimuth “−170.0” and theperpendicular angle Elevation “4.9” are the horizontal angle φ″calculated as represented by Equation (16) and the perpendicular angleθ′ calculated as represented by Equation (2), respectively.

In the example depicted in FIG. 16, the relative positional relationamong all the objects OBJ1 to OBJ6 before remapping is substantially thesame as that after remapping.

That is, it is understood that the object OBJ1 and the object OBJ2, theobject OBJ3 and the object OBJ4, and the object OBJ5 and the object OBJ6are bilaterally symmetric with each other with respect to the segmentthat connects the origin O to the central position of the reproductionscreen PSC11 in the horizontal direction even after remapping.

A pattern diagram of the positional relations among the objects beforeremapping and after remapping in this example is that depicted in FIG.17. It is noted that parts corresponding to those in FIG. 1 are denotedby the same reference symbols in FIG. 17 and description of the partswill be omitted as appropriate.

In FIG. 17, the reference screen RSC11 and the object OBJ1 to the objectOBJ6 before remapping are depicted in parts indicated by arrows A51 andA52. More specifically, the reference screen RSC11 is located at theposition indicated by the uncorrected reference screen information, andthe object OBJ1 to the object OBJ6 are located at the positionsindicated by the uncorrected object position information.

On the other hand, the reproduction screen PSC11 and the object OBJ1 tothe object OBJ6 after remapping are depicted in parts indicated byarrows A53 and A54.

In this example, the reference screen RSC11 and the object OBJ1 to theobject OBJ6 before remapping indicated by the arrows A51 and A52 arelocated at the same positions as those in the example depicted in FIG.7.

Moreover, it is understood that in the parts indicated by the arrows A53and A54, the object OBJ1, the object OBJ3, and the object OBJ5 afterremapping are bilaterally symmetric with the object OBJ2, the objectOBJ4, and the object OBJ6 after remapping with respect to the segmentthat connects the origin O to the central position of the reproductionscreen PSC11 in the horizontal direction. That is, it is understood thatthe positional relation among the objects viewed from the centralposition of the screen before remapping is substantially the same asthat after remapping, and remapping has been performed appropriately.

Example of Configuration of Information Processing Apparatus

When performing the processes described above, the informationprocessing apparatus 11 is configured as depicted in, for example, FIG.18. It is noted that parts corresponding to those in FIG. 8 are denotedby the same reference symbols in FIG. 18 and description of the partswill be omitted as appropriate.

The information processing apparatus 11 depicted in FIG. 18 includes theoffset angle calculation section 21, the position information correctionsection 22, and the object remapping section 23.

In this example, the reproduction screen information is supplied to theoffset angle calculation section 21 and the position informationcorrection section 22.

The offset angle calculation section 21 calculates the offset angleφ_(offset_value). In addition, the offset angle calculation section 21calculates a horizontal angle formed between the front direction of theuser U11 present in the reproduction space, that is, the direction fromthe origin O to the reference position and a direction from the origin Oto the central position of the reproduction screen PSC11 as thereproduction screen offset angle φ_(repro_offset_value) on the basis ofthe supplied reproduction screen information. The offset anglecalculation section 21 supplies the offset angle φ_(offset_value) andthe reproduction screen offset angle φ_(repro_offset_value) to theposition information correction section 22.

The reproduction screen offset angle φ_(repro_offset_value) is ahorizontal angle Azimuth that indicates a misalignment amount of thecentral position of the reproduction screen PSC11 from the referenceposition in the direction of the horizontal angle Azimuth. That is, thereproduction screen offset angle φ_(repro_offset_value) is informationthat indicates an offset amount of the reproduction screen PSC11 fromthe reference position present in the front direction of the user U11.Note that the information that indicates the offset amount of thereproduction screen PSC11 is not limited to the reproduction screenoffset angle φ_(repro_offset_value) and may be any information.

The position information correction section 22 performs correction tonot only obtain the corrected reference screen information and thecorrected object position information but also obtain the correctedreproduction screen information. The position information correctionsection 22 supplies the corrected reference screen information, thecorrected object position information, the corrected reproduction screeninformation, and the reproduction screen offset angleφ_(repro_offset_value) to the object remapping section 23.

That is, the position information correction section 22 corrects thereproduction screen information supplied from outside on the basis ofthe reproduction screen offset angle φ_(repro_offset_value) suppliedfrom the offset angle calculation section 21, and obtains correctedreproduction screen information.

The object remapping section 23 performs remapping of the objectposition information, that is, each object position on the basis of thecorrected reference screen information, the corrected object positioninformation, the corrected reproduction screen information, and thereproduction screen offset angle φ_(repro_offset_value) supplied fromthe position information correction section 22, and outputs resultantobject position information.

Description of Remapping Process

A remapping process performed by the information processing apparatus 11depicted in FIG. 18 will next be described with reference to theflowchart of FIG. 19.

In Step S41, the offset angle calculation section 21 calculates theoffset angle φ_(offset_value) and the reproduction screen offset angleφ_(repro_offset_value) on the basis of the supplied reference screeninformation and the supplied reproduction screen information, andsupplies the offset angle φ_(offset_value) and the reproduction screenoffset angle φ_(repro_offset_value) to the position informationcorrection section 22.

Specifically, the offset angle calculation section 21 calculates theoffset angle φ_(offset_value) by conducting calculation represented byEquation (3). Furthermore, the offset angle calculation section 21calculates the reproduction screen offset angle φ_(repro_offset_value)by conducting calculation represented by Equation (12).

In Step S42, the position information correction section 22 corrects thereference screen information, the object position information and thereproduction screen information supplied from outside on the basis ofthe offset angle φ_(offset_value) and the reproduction screen offsetangle φ_(repro_offset_value) supplied from the offset angle calculationsection 21.

For example, the position information correction section 22 corrects thereference screen information and the object position information byperforming a similar process to the process of Step S12 in FIG. 11, andobtains the corrected reference screen information and the correctedobject position information.

Furthermore, for example, the position information correction section 22conducts calculation represented by Equations (13) and (14) on the basisof the reproduction screen offset angle φ_(repro_offset_value), therebycorrecting the reproduction screen information and obtaining thecorrected reproduction screen information.

The position information correction section 22 supplies the correctedreference screen information, the corrected object position information,the corrected reproduction screen information, and the reproductionscreen offset angle φ_(repro_offset_value) obtained as described aboveto the object remapping section 23.

In Step S43, the object remapping section 23 performs remapping of eachobject position on the basis of the corrected reference screeninformation, the corrected object position information, the correctedreproduction screen information, and the reproduction screen offsetangle φ_(repro_offset_value) supplied from the position informationcorrection section 22.

For example, the object remapping section 23 calculates the objectposition information that indicates the remapped position of each objectby conducting calculation represented by Equations (2), (15), and (16).The object remapping section 23 then outputs the object positioninformation obtained as described above to the subsequent stage, and theremapping process is ended.

In this way, the information processing apparatus 11 performs remappingafter correcting the reference screen information, the object positioninformation, and the reproduction screen information. The informationprocessing apparatus 11 then corrects the object position information byas much as a correction of the reproduction screen information. By doingso, it is possible to perform appropriate remapping without dependenceon the located positions of the reference screen RSC11 and thereproduction screen PSC11.

In the first embodiment and the first modification of the firstembodiment, the example of calculating the offset angle for thehorizontal angles and correcting the horizontal angles in each of thereference screen information and the object position information on thebasis of the offset angle has been described. However, a similar processmay be performed for not only the horizontal angles but also theperpendicular angles and the perpendicular angles in each of thereference screen information and the object position information may becorrected.

In such a case, an offset angle is calculated also for the perpendicularangles in a similar manner to the case for the horizontal angles. Theperpendicular angles in the reference screen information and the objectposition information are corrected on the basis of the calculated offsetangle, and remapping is then performed.

Likewise, also in the second modification of the first embodiment, theperpendicular angles in each of the reference screen information, theobject position information, and the reproduction screen information maybe corrected. Furthermore, the second modification of the firstembodiment may be combined with the first modification of the firstembodiment.

Moreover, it has been described so far that after the reference screeninformation and the object position information are corrected inconformity with the reference screen RSC11, the object positioninformation indicating the position of each object after remapping iscalculated using the corrected reference screen information and thecorrected object position information obtained by the correction.However, only the object position information, that is, the position ofeach object may be corrected in conformity with the reference screenRSC11.

In such a case, after the offset angle is calculated, the objectposition information is corrected on the basis of the offset angle andused as the corrected object position information. Subsequently, theremapping of each object position is performed on the basis of thecorrected object position information, the reference screen information,and the reproduction screen information. That is, the object positioninformation that indicates the position of each object after remappingis calculated.

Meanwhile, a series of processes described above can be either executedby hardware or executed by software. When a series of processes isexecuted by software, a program constituting the software is installedinto a computer. Here, types of the computer include a computerincorporated into dedicated hardware, a computer, for example, ageneral-purpose personal computer, capable of executing variousfunctions by installing various programs into the computer, and thelike.

FIG. 20 is a block diagram illustrating an example of a configuration ofthe hardware of the computer executing a series of processes describedabove by the program.

In a computer, a CPU (Central Processing Unit) 501, a ROM (Read OnlyMemory) 502, and a RAM (Random Access Memory) 503 are mutually connectedby a bus 504.

An input/output interface 505 is also connected to the bus 504. An inputsection 506, an output section 507, a recording section 508, acommunication section 509, and a drive 510 are connected to theinput/output interface 505.

The input section 506 includes a keyboard, a mouse, a microphone, animaging element, and the like. The output section 507 includes adisplay, a loudspeaker, and the like. The recording section 508 includesa hard disk, a nonvolatile memory, and the like. The communicationsection 509 includes a network interface and the like. The drive 510drives a removable recording medium 511 such as a magnetic disk, anoptical disk, a magneto-optical disk or a semiconductor memory.

In the computer configured as described above, the CPU 501 loads aprogram recorded in, for example, the recording section 508 to the RAM503 via the input/output interface 505 and the bus 504 and executes theprogram, whereby a series of processes described above is performed.

The program executed by the computer (CPU 501) can be provided by, forexample, recording the program in the removable recording medium 511serving as a package medium or the like. Alternatively, the program canbe provided via a wired or wireless transmission medium such as a localarea network, the Internet, or digital satellite broadcasting.

In the computer, the program can be installed into the recording section508 via the input/output interface 505 by attaching the removablerecording medium 511 to the drive 510. Alternatively, the program can bereceived by the communication section 509 via the wired or wirelesstransmission medium and installed into the recording section 508. Inanother alternative, the program can be installed into the ROM 502 orthe recording section 508 in advance.

Note that the program executed by the computer may be a program forperforming processes in time series in an order described in the presentspecification or may be a program for performing the processes either inparallel or at necessary timing such as timing of calling.

Moreover, the embodiments of the present technique are not limited tothe embodiments described above and various changes and modificationscan be made without departing from the spirit of the present technique.

For example, the present technique can have a cloud computingconfiguration for causing a plurality of apparatuses to process onefunction in a sharing or cooperative fashion.

Furthermore, each step described in the above flowcharts can be not onlyexecuted by one apparatus but also executed by a plurality ofapparatuses in a sharing fashion.

Moreover, when one step includes a plurality of processes, the pluralityof processes included in the one step can be not only executed by oneapparatus but also executed by a plurality of apparatuses in a sharingfashion.

Furthermore, the present technique can be configured as follows.

(1)

An information processing apparatus including:

an offset calculation section that calculates an offset amount of aposition of a reference screen from a reference position present in afront direction of a user;

a position correction section that corrects a position of an audioobject referred with the reference position, in conformity with theposition of the reference screen on the basis of the offset amount; and

a remapping section that remaps the position of the audio object inconformity with a position of a reproduction screen on the basis of thecorrected position of the audio object.

(2)

The information processing apparatus according to (1), in which

the offset calculation section corrects the offset amount by apredetermined correction value when the reference screen is placed in abackward direction of the user.

(3)

The information processing apparatus according to (1) or (2), in which

the position correction section adjusts a correction value used duringcorrection of the position of the audio object when a range ofinformation that indicates the position of the audio object is specifiedas a range within a predetermined range.

(4)

The information processing apparatus according to any one of (1) to (3),in which

the position correction section corrects the position of the referencescreen on the basis of the offset amount, and

the remapping section remaps the position of the audio object on thebasis of the corrected position of the reference screen and thecorrected position of the audio object.

(5)

An information processing method including the steps of:

calculating an offset amount of a position of a reference screen from areference position present in a front direction of a user;

correcting a position of an audio object referred with the referenceposition, in conformity with the position of the reference screen on thebasis of the offset amount; and

remapping the position of the audio object in conformity with a positionof a reproduction screen on the basis of the corrected position of theaudio object.

(6)

A program for causing a computer to execute a process including thesteps of:

calculating an offset amount of a position of a reference screen from areference position present in a front direction of a user;

correcting a position of an audio object referred with the referenceposition, in conformity with the position of the reference screen on thebasis of the offset amount; and

remapping the position of the audio object in conformity with a positionof a reproduction screen on the basis of the corrected position of theaudio object.

REFERENCE SIGNS LIST

-   11: Information processing apparatus-   21: Offset angle calculation section-   22: Position information correction section-   23: Object remapping section

The invention claimed is:
 1. An information processing apparatuscomprising: a bit stream input section that inputs a bit streamincluding a position of an audio object and a position of a referencescreen; an offset calculation section that calculates an offset amountof the position of the reference screen from a reference positionpresent in a front direction of a user; a position correction sectionthat corrects the position of the audio object referred with thereference position, in conformity with the position of the referencescreen on the basis of the offset amount; and a remapping section thatremaps the position of the audio object in conformity with a position ofa reproduction screen on the basis of the corrected position of theaudio object.
 2. A method comprising: inputting, by a bit stream inputsection, a bit stream including a position of an audio object and aposition of a reference screen; calculating, by an offset calculationsection, an offset amount of the position of the reference screen from areference position present in a front direction of a user; correcting,by a position correction section, the position of the audio object, inconformity with the position of the reference screen on a basis of theoffset amount; and remapping, by a remapping section, the position ofthe audio object in conformity with a position of a reproduction screenon a basis of the corrected position of the audio object.
 3. Anon-transitory computer readable medium on which is stored a computerprogram which, when implemented by a computer, cause the computer toimplement steps of: inputting, by a bit stream input section, a bitstream including a position of an audio object and a position of areference screen; calculating, by an offset calculation section, anoffset amount of the position of the reference screen from a referenceposition present in a front direction of a user; correcting, by aposition correction section, the position of the audio object, inconformity with the position of the reference screen on a basis of theoffset amount; and remapping, by a remapping section, the position ofthe audio object in conformity with a position of a reproduction screenon a basis of the corrected position of the audio object.